I have a 2011 MX YBB with 2011 XTR 2x10. I had to use the Shimano XTR M985 low clamp front derailleur. All good.

Be careful with your group choice. Moots made a change in Oct. of 2010 to allow for the new 2x10 XTR group. On the Mooto X YBB's made before that, the Shimano XTR group will not work (but SRAM 2 x10 will work if I recall correctly). Strongly suggest emailing Moots with your frame serial number and verify the date of manufacture. I had a few hiccups getting my ride up and running, but am loving it now.

Thanks. I actually have a frame that was manufactured before Oct 2010. I have an XX crank on now, but am running XT/XTR everywhere else. I think I should be good as if i recall, the crank was the issue.